Old man mixed glue and cake ingredient (6,5)

I believe the answer is:

almond paste

I'm a little stuck... Click here to teach me more about this clue!

'cake ingredient' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'old man mixed glue' is the wordplay.
'mixed' indicates an anagram.
'glue' becomes 'paste' (synonyms).
'old'+'man'='oldman'
'oldman' anagrammed gives 'almond'.
'almond'+'paste'='ALMOND PASTE'

'and' acts as a link.

Can you help me to learn more?

(Other definitions for almond paste that I've seen before include "Marzipan" , "part of the Christmas cake" .)

I've seen this clue in The Daily Express.

Want a hint initially instead of a full solution? Install my app